Attractions In New Orleans - Scientists Estimate How Much Longer The Earth Can Support Life

Source      - http://www.forbes.com/
By             - Alex Knapp
Category   - Attractions In New Orleans
Posted By - Homewood Suites New Orleans

Attractions In New Orleans

The end of the world is near! Well, relatively near, geologically speaking. Okay, even geologically speaking, it’s pretty far off.

But scientists at the University of East Anglia have made their best estimate for how much longer the Earth will be habitable for human life, barring nuclear war, rogue asteroids, or being destroyed to make room for a hyperspace bypass. Fortunately, you don’t need to put your affairs in order any time soon. The researchers estimate that the Earth will remain habitable for another 1.75 to 3.25 billion years.

Their research, which has been published in the journal Astrobiology, is part of the bigger project of looking for life outside of our own solar system. Over the past few years, astronomers have discovered a number of planets that exist within the habitable zones of their stars – meaning that their orbits place them not too far, but not too close, so that temperatures on the surface are just right for life to develop.

But with so many planets in potentially habitable zones, there has to be some priority in trying to determine which planets are most likely to contain life and are therefore more worth devoting additional resources to observing. That’s where this research comes in.

However, as the orbits of planets change over time, and as the nature of their stars change over time, no planet is likely to stay in a habitable zone forever. So in this paper, the astronomers did their best to estimate the “habitable zone lifetime” of a planet. Since life took hundreds of millions of years to evolve on Earth, the researchers reason that the best candidates for observation are those with the longest habitable zone lifetimes.

The researchers then studied 34 planets, including Earth, that are thought to exist within the habitable zones of their stars. They then used observations of their orbits and their stars’ to arrive at estimates of each planets habitable zone lifetime. There is an astounding range of possibilities – ranging “from significantly less than that of Earth to over five times Earth’s HZ lifetime,” they wrote.

Of course, this paper really represents a first step in determining how likely a planet is going to evolve life. The scientists themselves notes this in the paper, where they write “Interpreting the results that have been returned by this simple model should be done with caution. While we have sought to estimate a theoretically habitable zone lifetime, we do not claim that the time that a planet spends within the HZ is the only control over habitability.”

They also note that different planets will experience different factors, which will provide still further interesting effects on how life might evolve on them. “The actual HZ lifetime of any given planet is unlikely to be controlled solely by planetary surface temperatures, and individual worlds may experience a variety of divergent (bio)geochemical evolutionary histories, possibly resulting in markedly different planetary environments to that of Earth.”

First step it may be, it’s still a fascinating one. As the models for habitability get further defined, that may help astronomers find another planet with life that much sooner. Additionally, this research reminds us that though the end may be billions of years away, the ability of the Earth to remain home for human beings won’t last forever.

But if humans are still around when the Earth begins to move out of the habitable zone, we can always move next door.

“If we ever needed to move to another planet, Mars is probably our best bet,” lead researcher Andrew Rushby said in a statement. “It’s very close and will remain in the habitable zone until the end of the Sun’s lifetime – six billion years from now.”